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PHOTOGRAMMETRY IN EPHESOS - RECORDING BASIC SPATIAL DATA 
Stefan KLOTZ 
Austrian Archaeological Institute 
A-1190 Vienna, Franz Klein-Gasse 1 
AUSTRIA 
Email: Stefan.Klotz@univie.ac.at 
The presented project is a co-operation of the Department of Photogrammetry (TU Istanbul), the Institute of 
Photogrammetry and Remote Sensing (TU Vienna) and the Austrian Archaeological Institute (Vienna). 
KEY WORDS: Photogrammetry, Cultural Heritage, Archaeology, GIS, Orthoimage 
ABSTRACT: 
Ephesos, on the west coast of Turkey, has been one of the most important cities of the Roman empire. Here, Austrian archaeologists 
carry out research and excavation for more than a hundred years. The first and the last comprehensive geodetic surveying of the 
whole area of Ephesos dates back to the very beginning of the Austrian activities. Aim of the current project is to obtain a valid 
mapping of the region of ancient Ephesos with the neighbouring sanctuary of Artemis. Seven infrared aerial photographs form the 
fundamentals of the photogrammetric process. Contoureline, inclination and shaded relief maps were derived from a terrain model 
and research work done into ancient water conduits. A Mosaic-Orthophoto was generated from the arial images with help of the 
terrain model. This map, together with the revised photogrammetric line analysis and the city plan, the latter generalised for a scale 
1:5000, have been united in a GIS. 
1. INTRODUCTION 
Ephesos, on the west coast of Turkey, was one of the most 
important cities of the Roman Empire. Here, Austrian 
archaeologists have been carrying out research and excavation 
for more than a hundred years. The first and the last 
comprehensive geodetic survey of the whole area of Ephesos 
dates back to the very beginning of the Austrian activities 
(Schindler, 1906). 
Aim of the current project is to obtain a valid mapping of the 
region of ancient Ephesos including the neighbouring sanctuary 
of Artemis. Drawing up a digital terrain model, an orthophoto 
as well as a cartographic map are the pursued goals. A digital 
plan of the ancient city, generated by means of digitised plans 
and new surveying, was already available at the start of the 
project. 
In the following, the possibities and applications offert by 
spatial data will be shown at the example of Ephesos. 
2. ORIGINAL MATERIAL AND PRECONDITIONS 
Seven infrared aerial photographs taken in 1997 form the basic 
material of the photogrammetric process. The arial photographs 
were taken by Turkish authorities on the occasion of an 
inspection flight regarding the amount of standing timber: 
• aerial photograph format: 23 x 23 cm 
• imagescale: 1:15000 
• year of flight: 1997 
The stereographically evaluated model area covers a surface of 
approx. 32 km2. The details were interpretated in an area of 
18.4 km2, which includes the urban area of Ephesos with its 
city walls, the sanctuary of Artemis and the Ayasoluk with St. 
John’s Church and the castle. 
Due to this special purpose the photographs do not provide any 
geodetically measured controlpoints signalised in the course of 
the flight. For analysis it was therefore necessary to select 
natural controlpoints in the pictures, characteristics such as 
edges of roofs, traffic-line markings etc. were used, which then 
had been measured in the field by GPS (Global Positioning 
System). Therefore it was possible to implement the aerial 
photos in the Ephesos Referenence Frame 1998 (ERF98) in 
which all other surveying in Ephesos is made. The ERF98 is 
defined by the global reference frame (ITRF94). Measurements 
for the bundle adjustment as well as the entire further mapping 
were undertaken with an analytic plotter. Following the bundle 
adjustment a medium standard deviation of ±18 cm at position 
and ±25 cm at height (internal accuracy) resulted for the tie 
points (points visible in two or more photographs but without 
ground control). 
3. DATA AND ANALYSIS 
In the course of stereographic analysis the whole visible 
situation (vegetation, traffic zones, buildings, waters, etc.) was 
measured. In order to create a digital terrain model (DTM), a 
point grid by 20 x 20 m resp. 80 x 80 m (varies due to the 
character of the ground) as well as breaklines were measured. 
So a very detailed recording of the terrain structure was 
achieved. Apart from photogrammetric regular points and 
breaklines, terrestrial as well as GPS surveyed points and 
breaklines were also involved in order to gain the digital terrain 
model. This procedere proceeding a substantially increased the 
accuracy, especially for areas in close neighbourhood to 
archaeological sites. Finally, about 80 000 points were used to 
derive the DTM.. 
4. ORTHOPHOTO MAP 
Four orthophotos were generated from the aerial photographs 
with the help of the new terrain model. Then, these orthophotos 
were combined to one single orthophoto map (Figure 1). The 
resolution of the digital orthophotos is limited by the scale of